Rafael Nadal at his post-match press conference at Wimbledon.
The 2013 Wimbledon Championships will go done as the year of the upsets.
Some upsets, like Rafael Nadal losing in the first round, were more shocking than others.
Other upsets, like Sabine Lisicki's win over Serena Williams, were more thrilling than others.
Fans may relish the number of relative unknowns moving into the later rounds. However, eliminated stars are left to consider, "What if?"
What if Serena Williams broke Sabine Lisicki to go up 4-0 in the third?
Usually after a Grand Slam, it's the "also-rans" and the "upstarts" who are left to ponder the what ifs. But this Wimbledon fortnight, it's the stars, the perennial powerhouses, with the biggest what ifs.
Maria Sharapova struggled with her footing at Wimbledon.
After her second-round loss to Michelle Larcher de Brito, Maria Sharapova talked about her uncharacteristically bad footing.
She fell three times during her match. By the end of that day, a record seven players had withdrawn or retired from the tournament because of injuries.
Even Sharapova's opponent stated the grounds were hazardous. Larcher De Brito told ESPN that, "She fell pretty hard, and I know that these grass courts can be quite slippery, quite dangerous...There's a lot of grass that's been cut that hasn't been swept away."
Of course, everyone played on the same grass. But falling leaves a player physically and psychologically fragile.
Makes you wonder, if Sharapova had not lost her footing, would she have been bounced in the second round?
Roger Federer courtside at Wimbledon
Roger Federer had several chances to change momentum in his stunning second-round loss to Sergiy Stakhovsky, but none appeared more important than an opportunity for Federer to break while up 6-5 in the fourth.
Stakhovsky was serving to stay in the set. His old-school serve-and-volley style threw Federer off.
"I had my opportunities, had the foot in the door. When I had the chance, I couldn't do it," Federer told ESPN.
Had he won the fourth set, that would have put tremendous pressure on Stakhovsky. Would it have been enough pressure? The odds are in Federer's favor when it comes to winning five-setters. He wins 75 percent of them.
Rafael Nadal in the first round at 2013 Wimbledon.
The winner of the French Open has so little time to recover before Wimbledon. They have to stay behind for interviews, public appearances and photo shoots. By the time they finish their obligations to the French Open, draws are being announced at Wimbledon.
There's a reason it's so difficult to win the French Open and Wimbledon back-to-back, though Nadal said neither scheduling nor his injuries were an excuse.
After the match he told USA Today, "Six hours ago was a perfect calendar, now is a very negative calendar."
Perhaps with a little more gas in the tank, Nadal would not have come up empty in the first round.
Victoria Azarenka during the first round at Wimbledon.
With all of the lower-ranked players left in the tournament, Victoria Azarenka has probably wondered about the missed opportunity at this year's Wimbledon.
What if Azarenka hadn't injured herself in her first round?
With Sharapova out of the way, this might have been Azarenka's best chance to win at Wimbledon.
Azarenka suffered a knee injury when she slipped and fell awkwardly in her first-round match.
Visibly shaken, Azarenka appeared to be crying after her fall. She withdrew before her second-round match.
An angry Azarenka blamed the courts. She told the The Independent, “My opponent fell twice and I fell badly on there [Court No1]. So did a lot of people after... It would be great if someone from the All England Club examines it and tries to find the issue, to see what happened.”
The All England Club issued a statement that read: "There have been no changes in the preparation of the courts and as far as we are aware the grass surface is in excellent condition."
Tell that to Azarenka, who saw her Wimbledon hopes take a tumble when she hit the turf.
Serena Williams in her fourth-round match against Sabine Lisicki.
After losing the first set 2-6 to Sabine Lisicki, Serena Williams came out in the second set on fire.
Relentless in her attack, Williams took the second set 6-1. She got off to a 3-0 lead in the decisive third set and was in a position to go up 4-0.
Credit goes to Lisicki, who played a brilliant game. But Williams got tight. Instead of playing to win, she began playing it safe.
This time her opponent was the aggressor. Lisicki took it to Williams.
So often the more aggressive player, this time Williams played passively.
After her loss, Williams spoke to NBC Sports about being aggressive. "If I want to be successful, if I plan on being successful, I’m never going to do it backing off," she said. "I have to play the game I can play. For me that’s being more aggressive.”